A dual-clutch transmission, (DCT) (sometimes referred to as a twin-clutch gearbox or double-clutch transmission), is a type of semi-automatic or automated manual automotive transmission. It uses two separate clutches for odd and even gear sets. It can fundamentally be described as two separate manual transmissions (with their respective clutches) contained within one housing, and working as one unit. They are usually operated in a fully automatic mode, and many also have the ability to allow the driver to manually shift gears, albeit still carried out by the transmission's electro-hydraulics.
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